import { defineStore } from "pinia";
import { computed, ref } from "vue";
import { useUserStore } from "./userStore";
import { insertCartAPI, findNewCartListAPI, delCartAPI } from "@/apis/cart";

// 封装购物车模块
export const useCartStore =  defineStore('cart', () => {
  // 接收登录信息
  const userStore = useUserStore()
  const isLogin = computed(() => userStore.userInfo.token)

  // state 购物车列表数据
  const cartList = ref([])
  // 获取最新购物车列表
  const updateNewList = async () => {
    const res = await findNewCartListAPI()
    cartList.value = res.result
  }

  // action 
  // 添加购物车
  const addCart = async (goods) => {
    const { skuId, count } = goods
    if(isLogin.value) {
      // 登录之后的加入购车逻辑
      await insertCartAPI({ skuId, count })
      updateNewList()
    } else {
      // 未登录
      const item = cartList.value.find((item) => goods.skuId === item.skuId)
      if (item) {  // 已添加过，count+1
        item.count++
      } else {  // 未添加过，直接push
        cartList.value.push(goods)
      }
    }

  }

  // 删除购物车
  const delCart = async(skuId) => {
    if(isLogin.value) {
      await delCartAPI([skuId])
      updateNewList()
    } else {
      const idx = cartList.value.findIndex((item) => skuId === item.skuId)
      cartList.value.splice(idx, 1)
    }
  }

  // 清除购物车
  const clearCart = () => {
    cartList.value = []
  }

  // 单选功能
  const singleCheck = (skuId, selected) => {
    const item = cartList.value.find((item) => skuId === item.skuId)
    item.selected = selected
  }

  // 全选功能
  const allCheck = (selected) => {
    cartList.value.forEach(item => item.selected = selected)
  }

  // 计算属性
  // 计算总数量
  const allCount = computed(() => cartList.value.reduce((a, c) => a + c.count, 0))

  // 计算总价
  const allPrice = computed(() => cartList.value.reduce((a, c) => a + c.count * c.price, 0))

  // 已选择数量
  const selectedCount = computed(() => cartList.value.filter(item => item.selected).reduce((a, c) => a + c.count, 0))
  // 已选择商品价钱合计
  const selectedPrice = computed(() => cartList.value.filter(item => item.selected).reduce((a, c) => a + c.count * c.price, 0))
  // 是否全选
  const isAll = computed(() => cartList.value.every((item) => item.selected))

  return { 
    cartList,
    updateNewList,
    addCart,
    delCart,
    clearCart,
    singleCheck,
    allCheck,
    allCount,
    allPrice,
    selectedCount,
    selectedPrice,
    isAll 
  }
}, {
  persist: true
})